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Thread: 6.4 earthquake between Bakersfield and Las Vegas

  1. #1
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    Sep 2004
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    6.4 earthquake between Bakersfield and Las Vegas

    Scattered damage, no fatalities reported, possibility of 2nd quake; earthquake monitoring system DID NOT warn

    https://www.cnn.com/2019/07/04/us/so...ake/index.html

  2. #2
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    Oct 2011
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    Fresno, CA
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    We got a nice 20-second or so roll in Fresno. It made our nearly 50-year-old house creak a little. I was sitting at my computer and my wife was sitting on the edge of the bed. She had just gotten up because we were out late last night with our astronomy club. Friends and family reported feeling the quake in Bakersfield, Pismo Beach, Sherman Oaks, Corona, etc.

    This was our second earthquake in two weeks. We recently took our oldest granddaughter on a driving vacation to Oregon--both as a reward for turning ten and to help celebrate one of my wife's friend's 60th birthday. We were in Eureka having dinner when the Portola quake hit. This was my granddaughter's first earthquake. She didn't know how to react at first.

  3. #3
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    My cousin was in a movie theatre at the time--watching the climax of the new Spider-Man movie.
    _____________________________________________
    Gillian

    "Now everyone was giving her that kind of look UFOlogists get when they suddenly say, 'Hey, if you shade your eyes you can see it is just a flock of geese after all.'"

    "You can't erase icing."

    "I can't believe it doesn't work! I found it on the internet, man!"

  4. #4
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    I saw some footage of this on the news. The thing that freaked me out was the sloshing pool. That's not some artificially tall structure; that's all ground-movement.

    Questions:
    What magnitude of ground movement caused this in particular and in general?
    How many inches laterally would the ground have been moving to cause this slosh?
    How much of the sloshing is due to actual lateral shifting of ground versus a cumulative resonance effect?

  5. #5
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    Quote Originally Posted by Gillianren View Post
    My cousin was in a movie theatre at the time--watching the climax of the new Spider-Man movie.
    Heh. How long did it take for the audience to figure it out?
    (Wow, these new subsonic sound systems are great! Wait a minute - this is a dialogue scene...)

  6. #6
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    6.9 quake has hit. Breaking news.

  7. #7
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    Could these be foreshocks of a 9.0?
    SHARKS (crossed out) MONGEESE (sic) WITH FRICKIN' LASER BEAMS ATTACHED TO THEIR HEADS

  8. #8
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    Quote Originally Posted by Roger E. Moore View Post
    6.9 quake has hit. Breaking news.
    I warned them not to place the news on the top shelf.

  9. #9
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    NEOTP Atlanta, GA
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    Now reported by the USGS as 7.1. That is major...

    https://earthquake.usgs.gov/earthqua...7511/executive

  10. #10
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    I am not sure but I think that you have to calculate the magnitude and the depth to see how much shaking there will be. The Japan earthquake in 2011 was huge in terms of magnitude, about 9, but it didnít destroy many buildings outright because it was quite deep and at sea. Of course, the effect it had on the ocean caused devastation due to the tsunami.


    Sent from my iPhone using Tapatalk
    As above, so below

  11. #11
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    Horrendous nonchalance at sports events during the 7.1 quake: players in many games interrupted by quake simply don't give a dang.

    https://deadspin.com/heres-what-sout...uak-1836149188

  12. #12
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    Quote Originally Posted by Spacedude View Post
    I warned them not to place the news on the top shelf.
    Look for the breaking news at 8 seconds in.

    https://www.youtube.com/watch?v=V5E-0Dix440

  13. #13
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    Some geologists have for a while thought that perhaps the San Andreas is becoming locked and the plate boundary will shift eastward to a seismically active corridor that roughly follows US Hwy 395 through the Owens Valley just east of the Sierra Nevada (sometimes referred to as 'Walker Lane'). Most of the bigger earthquakes in Southern California lately have been along this axis rather than the San Andreas, including these two near Ridgecrest. In the southern part of this corridor lies the Southern California Shear Zone, a very seismically active region.

    Although hardly conclusive, the geometry of the SA system supports this hypothesis. Just north of Los Angeles, the SA 'bends', which has caused the Transverse Ranges to uplift. It also has caused the Garlock Fault to form. The Garlock runs east-west from the SA to the Shear Zone and forms the northern boundary of a large rotating fault block. As the Pacific Plate slides past the North America Plate, this bend impedes that movement. It makes sense that stress would be relieved somewhere else, somewhere less impeded. The hypothesis loses a bit of steam as you follow the 395 corridor up towards Reno Nevada where there is relatively scant evidence for plate boundary activity. I also wonder how the massive Sierra Nevada batholith (the underlying core of the mountain range) would affect things. But give it a few million years and Las Vegas could be a coastal city.

  14. #14
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    CNN Live-news stream on earthquake situation. Thousands of small aftershocks, significant change for 6.0+ quake, 3% chance for 7.0+.

    https://www.cnn.com/us/live-news/cal...ntl/index.html

  15. #15
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    Sep 2004
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    Local news from SoCal, Los Angeles Times, much structural damage

    https://www.latimes.com/local/lanow/...705-story.html

  16. #16
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    Oct 2011
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    Fresno, CA
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    On the night of the 3rd (see above), my wife and I were at Big Stump in Kings Canyon National Park for a night of observing with several other club members. I had my 11" Celestron SCT and she had her 10" Orion Dob. I went back on the night of the 5th by myself to work on the rest of the observing plan that I wasn't able to finish on the 3rd.

    Before the sky got dark enough for observing deep sky objects, I was mostly looking at the Moon, Jupiter, and a few of the brighter double stars, as well as entertaining several groups of tourists. At 8:19 p.m., I was looking at the Moon at 215x when all of a sudden the Moon started to wiggle in the eyepiece. My first thought was, "why is the scope jiggling when there is no wind?" Then I realized my body was moving too and figured out it was a new quake and probably related to the 6.4 the day before. That's the first time I ever experienced an earthquake strong enough to affect the Moon.

    My wife told me the next day that our pool had sloshed water onto the decking at each end.

  17. #17
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    Quote Originally Posted by DaveC426913 View Post
    I saw some footage of this on the news. The thing that freaked me out was the sloshing pool. That's not some artificially tall structure; that's all ground-movement.

    Questions:
    What magnitude of ground movement caused this in particular and in general?
    How many inches laterally would the ground have been moving to cause this slosh?
    How much of the sloshing is due to actual lateral shifting of ground versus a cumulative resonance effect?
    https://en.m.wikipedia.org/wiki/Seiche#Lake_seiches
    "Swimming pools are especially prone to seiches caused by earthquakes, as the ground tremors often match the resonant frequencies of small bodies of water. "

  18. #18
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    Feb 2005
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    As a kid, I used to make my own in the bathtub--getting the water to slosh just so.

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